. Interventions for children with autism spectrum disorders (ASD) that have proven efficacious in research settings generally have not been effectively implemented in community settings. Challenges to successful implementation of interventions are apparent in AIMS (Autism Instructional Methods Study), an ongoing, randomized trial designed to test the effectiveness of an efficacious, teacher-delivered, curriculum-based intervention for children enrolled in autism support classrooms in a large, urban school district. Early observations suggest that a key reason for this variability is the extent to which the teachers perceive that their use of the intervention is expected, supported, and rewarded by their supervisors and other classroom staff. This shared perception is referred to as the organization's implementation climate. While a rich literature examines the role of the implementation climate in business settings, there is little study of the unique implementation climate in health and human services in general, and special education settings specifically. The proposed study will examine the impact of 1) administrative and education support staffs acceptance of the intervention and 2) the climate of autism support classrooms on the ongoing implementation of an evidence-based intervention and subsequent student outcomes. To address these aims, school principals and classroom assistants will report their acceptance of and support for the intervention, teachers will report on classroom implementation climate, and direct measures of program fidelity and child outcomes from the ongoing trial will be used. If successful, this project will advance our understanding of the best ways to support the implementation of efficacious interventions in special education settings. It will apply, for the first time, conceptual models and tools developed in business contexts to special education settings, with the goal of quantifying the extent to which the school and classroom environment supports or impedes intervention implementation. This study provides a strong foundation for intervention research targeting organizational climate as a way to support the implementation of evidence-based interventions, with the goal of improving services and outcomes for children.